


Beats From an Immortal Heart

by Dinahdog



Category: Adventure Time
Genre: F/M, Figthing, Love, Mushroom War, Nightosphere, Romance, Stuff, Violence, fiolee, theory, vampire
Language: English
Status: Completed
Published: 2012-02-05
Updated: 2012-02-05
Packaged: 2017-11-06 16:58:22
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 10
Words: 10,792
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/421200
Author URL: https://archiveofourown.org/users/Dinahdog/pseuds/Dinahdog
Summary: <blockquote class="userstuff">
              <p>Marshall Lee never thought he'd fulfill an ancient curse placed on him years ago, but now that he's met Fionna, he finds that his heart beats more than figuratively for her. In a desperate attempt to regain his immortality, he sets out on a journey to the Nighto'sphere where both he and Fionna are faced with great peril, moral conflicts, and near-death.</p>
            </blockquote>





	1. Aaa, Ooo, and the Nighto'sphere

**Author's Note:**

> I wrote this before the Hunson Abadeer episode, so the geography of the Nighto'sphere isn't accurate, but gah I am way too lazy to fix it now. This first chapter is all theory and there is an OC in this (the bad guy) so if you're like uber against those, just a warning.

The sun shone down brightly in the land of Aaa. It was always bright and sunny here, the perfectly green grass swaying in the breeze, tickling Fionna's legs. Sitting next to her with an umbrella in hand was her friend, Marshall Lee, the Vampire King. Marshall was very old for his young appearence and attitude. That was due to the fact he was immortal of course. Marshall looked out over the rolling hills, the triangular peaks of the Ice Kingdom's mountains in the distance.

"Hey Marshall?" Fionna looked up and into his pitch black eyes. He raised an eyebrow at her.

"Yeah?"

"I was wondering, how old are you?" Marshall blinked for a minute. He smirked at her.

"1000 years. Why?" Fionna did the math on her fingers the best she could. She was always terrible at it.

"So...You lived during the Mushroom Wars?" The usually playful and relaxed Marshall went serious, a solemn look on his face, the memories of that horrific time coming back to him.

"Yeah, I did. The end of them, anyway." He didn't look at Fionna, her blue eyes batting at him. It was silent for a moment.

"Do...Do you remember anything?" He didn't answer and for a moment, and Fionna thought she had offended him.

"Yes. Do you want to hear about it?" he sighed. He smirked at her, as though her sudden curiosity in such a violent subject was appealing to him. She nodded her head vigurously and he smiled even more, showing his fangs. "Very well then." He leaned in close to her, only a few inches from her face. He sneered as if telling a scary story around a camp fire.

"Before we called this world Aaa, the planet was called Earth. Greatly detailed beings called humans roamed it, in control of all other species. There were no candy people or vampires or rainicorns. Humans and a few animals. Most of the world at this point had been stripped of all natural resources. Countries went to war, fighting over any land that still had what they needed. The nuclear warfare between them began to change the way we looked. Details began to disappear and we shifted into a 2D form. Have you ever heard of 3D? Probably not. It's a very hard concept to grasp." Fionna stared at Marshall Lee, wide-eyed and interested. "Anyway, in this change, several new creatures were created. Mostly mutants of people. This included the undead and vampires."

"What about candy people?" Fionna asked.

"Oh no, not yet. Not that farly mutated. Don't worry, they come in later. My grandfather was one of these mutants. These undead are not like the usual ones you hear about. They weren't zombies. They just happend to be immortal and didn't have a beating heart. His name was Marcus. He roamed the land in vain, looking for someone like himself. He found a woman named Resputia. They married and had a son. This son...is my father." He spat the last word, glaring past Fionna at the idea of him. All of his joking manner on the subject disappeared. "Since the Earth was in such a state of chaos, my grandparents feared raising their son here. Using their immortal abilities, they opened up a whole new universe, connected to the planet. They found that the warring states stopped in the night and peace would come over the land. So they made their new world dwell in the night and named it the Nighto'sphere." Marshall paused and looked at Fionna. Her mouth was gaping open. "What?"

"You mean you grandparents created the Nighto'sphere? That's totally rad!" Marshall laughed and rolled his eyes.

"Yes, they did. My father grew up there. My grandparents thought he was safe, but because his mind was young, it still absorbed that of which was around it. The chemicals and evil happening in Aaa leaked into the Nighto'sphere and encased my father. These same chemicals seemed to react with something in the Nighto'sphere. Legend has it, another universe, much like ours, was created. Many people were paralelled. Granted, the world is a few years behind our own. They called it Ooo. When my father was 25 years of age, he supposedly found the entrance to Ooo. He then killed his father, gaining his immortality and domain over the Nighto'sphere. My grandmother was left helpless and became his servant. Realizing she'd have to serve him for eternity, she escaped the Nighto'sphere and went into hiding. My father tracked her down and executed her." Fionna's face was solemn now, and she looked down, realizing just how evil Marshall Lee's father was. He continued. "It was during this hunt on Earth that he met my mother. She was only a mortal, but my father fell in love with her anyway. They were married and soon, had a child."

"You?" asked Fionna. But Marshall shook his head.

"No. They had a daughter. Her name was Marceline. She was a mortal like our mother, but when she turned 18, my father had her turned into an immortal. There are several types of immortal you can become. Like me, she chose vampire. She drank blood like my father, but found it distasteful. She couldn't stand to kill anyone. The Mushroom wars had quieted down now, most of the humans extinct," he glanced at Fionna and winked. She blushed and he smirked before continuing,"and the waste and hatred no longer leaked through. She had a slight evil seed from our father's influences, but not enough. She found she could sustain herself on shades of red. But to go against evil's way was disrespectful and she was looked down upon. My father said he'd have to banish her if she did not perform an evil act. To prove herself, she killed the Vampire Queen. She gained the title of Vampire Queen and went to go live in the land of Ooo. My father tried to make her stay, but our mother helped her escape. My father found out and banished her to Aaa. My mother left and remarried. My father became lonely and went after her, only to find he was too late. Broken-hearted, he killed her and her lover and stole thier souls. This is why he hates mortals and how he gained the ability to eat souls. I had been born by then, of course." He paused and looked out over the horizon. The sun was beginning to set and Marshall Lee could almost set down his umbrella and be safe. Almost.

"I was two years younger than my sister. We were both very close to our mother since our father was constantly away on business trips. When my sister left the Nighto'sphere, my father cast a spell on me so that I'd forget she ever existed. I only had one memory of her left and asked everyone in the Nighto'sphere about her. They were not to tell me, but I eventually found someone who told me everything. The memories flooded back. That man was later executed. I still feel reponsible for his death. I became a vampire when I was 18 and was automatically crowned the Vampire King, seeing as there wasn't one yet. I taught myself to survive on shades of red, a new hatred for my father growing inside of me. I knew when he found out and ran to Aaa, away from the Nighto'sphere."

It was dark now and Marshall Lee put his umbrella away. Fionna looked like she was about to cry, but the adventuress was tougher than that and she sucked it in.

"So...This whole para-whatever universe thing, what do mean by it? There's another one of me?" Marshall nodded.

"Yes, but a guy." Fionna furrowed her eyebrows, obviously in deep thought. "Oh, and younger," he added. She was really confused now and looked helpless as she tried to think about it. Marshall laughed. "Ooo is a few years behind us, dim-bat. You're 15, right? That means he's probably 12 or so." She seemed to relax ever so slightly, but was still deep in thought.

"So, does that mean there's a girl of you?"

"No, because I was born in the Nighto'sphere. I visited Aaa a lot though. It was a wasteland for the longest time. The candy people had actually been mutated children. The children of drafted parents buried candy in the ground to hide it from others. When the abandoned children fell asleep over their sugary treasure, radiation caused them to sink into the ground and mold with the candy, turning them into candy people." Fionna seemed very interesed in the subject of the candy people, but Marshall didn't care for them. He shriveled up his nose and snorted.

"The only other creatures to live from that far back are the rainicorns. They live for very long amounts of time, but they're not immortal. Just old." They laughed and sighed, looking up at the stars.

"I wonder how you get to Ooo...," Fionna wondered out loud.

"Only my father knows. What an adventure that'd be, though."

"Yeah." Fionna yawned and leaned against Marshall before finally falling asleep. Marshall Lee sighed and grabbed her in his arms, holding her close to him. He flew her to the treehouse, going through the upstairs window and lying her on her bed. He looked at her peaceful face for a moment before flying back out the window and to his cave.


	2. Chest Pains

_Drip, drip, drip._

_Water dripped from the stalagmites, little lonely puddles forming in the dents and crevices of the cave floor. Marshall Lee couldn't see well. His father had many enemies, but he knew this one would satisfy his need. He was going to get him back this time. Those were HIS fries and, sure enough, his father had to put his grimy fingers in them. Didn't he have souls to eat instead? Marshall wouldv'e shared, but the moment he left the room, his stupid dad had eaten them all. He finally reached the opening to her tomb. He said those special words, a lost language know as latin. It rumbled and opened and she lie there in stone, frozen by his father. He smiled a wicked grin and poured the solution on her. The cement casing cracked and broke, chunks falling away. She only sat there for a moment, unmoving. A snake pulsed and she twitched a tentacle. She opened her eyes and stared down the Vampire King._

_"Marshall Lee? Son of the overlord of the Nighto'sphere and King of Vampires? What brings a kindly soul like yours here?" she hissed, her tongue snipping out like the snakes that slithered on her head._

_"My father. He does not respect me and I hate him. I want you to harm him, show him what he deserves. Kidnap his beloved raven, Gardsque. Release him into Aaa. He's pretty dumb so he should just fly away."_

_"And in retuuurn?"_

_"Give me an offer."_

_"How about this? You are not allowed to fall in love, Marshall Lee. If you do, your heart shall begin to beat again, and although you will keep all your current powers and never age, you can die. Your heart is now mine, Marshall Lee, Vampire King." The beast swiped Marshall's chest with a slimy tentacle, the acid-like slime burning even the skin of the immortal vampire. He didn't flinch or twitch as her symbolic scar burned it's way into his chest, marking her possession over yet another doomed heart._

"WOOOOOOO!" Fionna screamed. She gripped onto the fur of the wolf with one hand, the other above her head like an excited roller coaster rider. Marshall Lee sped along the ground, weaving in and out of the running group of wolves. He laughed as the exhilaration made him light-headed and giddy. He swerved away from the pack and above them as they came to a halt at the end of a cliff, stopping to howl at the full moon in all it's night time glory. Fionna laughed from the pure excitement as the wolves went running down the hill, the rocks rumbling down along side them. Marshall swooped down, yanking Fionna from her perch on one of the wolves. She was still laughing as he flew up farther and farther, the wolves running into the forest. Their howls echoed through the night and the growing cold nipped the adventuress and the vampire's noses as they began to pass through the Ice Kingdom.

"Hahahaha! Wooo!" Marshall smiled at her. She had one of those awkwardly cute laughs that just made you smile every time you heard it.

"Did ya have fun?"

"Heck yeah I did! That was totally awesome, dude! When can we do it again? Huh? When?" Marshall laughed this time.

"You're like a kid on Christmas." Fionna raised an eyebrow at him.

"Uh...what's Christmas?" Marshall looked at the 15 year-old girl. He forgot he was 1000 years old sometimes. Especially with Fionna. She made him feel young, like he was the age he looked. Marshall's chest had a small and sudden twang of pain and he gasped, but it passed quickly.

"You okay Marsh?"

"Huh? Oh, yeah, I'm fine. Probably just the cold." Fionna smiled up at him, pointing a finger at herself.

"I'M not cold. I've got enough fat to keep me warm." Marshall rolled his eyes.

"You're not fat, you're chubby, and it's adorable." Fionna glared at him.

"Don't call me adorable, skinny!"

"Adorable, worable, wittle Fionna," he smirked. She punched him in the arm and he laughed.

"Put me down!" Her face was beginning to turn pink.

"Alrighty then." He let go of her and she yelped for a moment before yelling back up,

"MARSHALL!" He laughed, zipping down after her and catching her with ease. She huffed, not affected at all by the over-used trick. "You're a tardmuffin, Marshall Lee!" He laughed again but stopped when she shivered ever so slightly in his arms. He realized he could see their breaths now.

"Oh, jeeze, I am a tardmuffin. You cold?" Fionna shook her head, but he could feel the icyness of her skin. He reached into her pack, pulling out a yellow sweater. "Please, put this on. I'm not about to get scratched to death because I brought you back as a Popsicle." She sighed and slipped it over her head. It gripped to her body and Marshall looked in front of him. They glided along in silence as they got farther and farther from the Ice Kingdom. Fionna slipped her sweater off and yawned. She cuddled up into Marshall and he smiled ever so slightly. He flipped onto his back, allowing her to sit on him like a floating chair. She leaned her head on his chest and fell asleep. Her quiet breaths were a soothing sound and the beating of her heart made his own, unmoving one, ache.

He slowed down and, slowly and gently so not to wake her, put his hand on the back of her head in a comforting gesture. Fionna was, by technicality, 3 years younger than his current state. Yet he found himself feeling for her, wanting to be with her. His last girlfriend, Ashley, had turned out ot be a selfish liar, absorbed in her witchcraft. She had sold his blankey from childhood to a stupid old warlock to get a weird wand. He had hid that blanket, too, but she found it. He clenched his other hand and breathed out, forgetting the memory. Fionna was different than Ashley, though. Fionna cared about others and she was good and pure. Marshall Lee had always been attracted to those who followed the ways of evil and darkness, so his attraction to Fionna had caught him off guard. He denied it for the longest time, but he found again and again that he wanted nothing more than to be with her.

He finally reached the tree house. This wasn't the first time Marshall had to carry a sleeping Fionna home through the window. She use to fall asleep on accident at first, always apologizing for it later, but now it just seemed a natural occurrence. Fionna was always so busy fighting monsters and saving stupid Prince Gumball from the Ice Queen that she didn't get much time for sleep. But when she was with Marshall, she was relaxed and protected, giving her the perfect opportunity to sleep. He laid her down gently, pulling off her shoes and backpack and putting the covers over her. He knew she still slept in her silly bunny hat, so he didn't take it off. He had never seen Fionna's blond hair all out before. He watched her for a moment and sighed. He bent down and kissed her forehead before floating back out the window. Fionna peeked open an eye and watched him float away, her cheeks red in the light.


	3. The Dream

**Notes for the Chapter:**

> Sorry, this chapter is short :I

Marshall Lee didn't technically have to breath or sleep. He didn't even have to eat or drink shades of red. The red kept him powerful, allowing him to do things like float and shape-shift. But he found he enjoyed doing these things, especially sleeping. He usually slept during the day, but he felt a strange sort of tired. So he floated over to his closet, slipping off his favorite red sneakers and his flannel shirt and blue jeans. He sighed and collapsed onto his bed, wearing nothing but his boxers. He turned the light out on his bedside table before crawling under the sheets and drifting to sleep.

_Marshall Lee was running through a dark cave, one he had been in before, but never down this part of it. Her cave had always been a labyrinth and he was lucky to have been there when they buried her, remembering the exact path, which turn to take and which one to avoid. But now he couldn't get out. He was panicing and was going out of breath as he sprinted down the lumpy path. She laughed manically and slime dripped from the walls. He tripped, scratching his knee, a little blood bubbling out. He turned around, his breath coming in short, quick gasps now._

_"I told you your heart was mine Marshall Lee. You knew the price you had to pay, and now, you've paid it." She laughed again and he got up, trying to float. He was slowly losing all of his powers, even his skin began to regain it's fleshy color. She pulled out a deadly gold arrow from her quiver, pulling it back in her bow. She was known for her accurate aim. She could've shot him with her eyes closed. The arrow went straight through his chest, blood spurting out. He gasped, but the air was stuck in his lungs. His heart beat around the long rod piercing through it, unable to process any blood. He collapsed to his knees and fell down. She slithered over and looked down at him._

_"What a waste. To think you were a king. A pity indeed. If you were that easy to take down, then I'm sure your lover shall be nothing more than a bug to squish in comparison."_

_"No-" Marshall tried to say. His voice was cut off by the pain in his chest. She turned now, looking over her shoulder once more. Marshall stretched his hand out, doing anything he could to stop her. "Please," he said, "I love her."_

_"And that's why you're weak, Marshall. Only mortal hearts fall for something as stupid as love." She began to go blurry as Marshall closed his eyes..._

Marshall sat straight up in bed, his heart pounding in his chest.


	4. Brought Back to Life

Marshall Lee was pacing in front of Fionna's door. He was walking for once, too nervous to fly. What if his powers gave out and he fell to the ground? He was mortal now and he wasn't about to let a long drop kill him. He held an umbrella, the sun still stinging his skin. She said he'd keep all his remaining powers. What about the dream, though? He was impatient and rapped on the door again. Geeze, how hard did those two sleep? He finally heard the door knob squeak as someone turned it. He stood in front of it, trying to act calm. It was hard to do when he could hear his heart pounding in his ears. Fionna stretched, yawning from being up so early. The little bit of hair sticking from her hat was messy and the hat had shifted on her head. She still wore the same clothes from yesterday.

"Marsh? What are you doing here? It's like, 6 am." she was rubbing her eyes, obviously still trying to wake up.

"It's an emergency, dude. I need your help. Now." He grabbed her hand, pulling her next to him.

"Wha-?" Marshall wrapped his arm around her, flying up into the air, the umbrella still above him. He flew at hyper speed to his cave, setting Fionna down gently before landing and closing his umbrella.

"Gosh, you think you could've let me get dressed first or at least put some shoes on?" Fionna straightened out her skirt and hat, thankful she was not in her pajamas at least.

"No time for that. I could be gone any second now. I'm in mortal danger here, Fi." Fionna instantly took a defensive stance.

"Who's trying to get you? I'll kill them! I'll go get my sword and we'll fight them off, I-" Marshall shushed her. She looked hurt, but stopped. Marshall's heart skipped a beat as he looked at her broken expression. Now wasn't the time for this. He shook his head.

"No, mortal danger, Fi. As in, I'm not immortal anymore. My heart beats again." He took her hand and placed it on his heart. She felt the little thumps as they moved to a rhythm. She gasped quietly.

"What- What happened?" she asked.

"I made a pact a long time ago with an evil being that said if I fell in love, my heart would start beating again."

"Two things: One, who are you in love with and, two, why is that so bad?"

"This woman is evil. Now that I'm alive again, she's going to hunt me down and kill me. It's just how it works."

"I see. Who's the girl?" Marshall blushed, trying to think of something.

"Um, uh, you don't know her. Her name's, um, Fi...Fiendly! Yeah." Fionna raised an eyebrow at him.

"Fiendly? That's a strange name. Isn't that a bad guy or something?"

"Yeah, but she's from the Nighto'sphere."

"What's she like?"

"Uhh...She has, er, blond hair and, ummm, a green skirt and a blue backpack." Marshall bit his lip, hoping his terrible lie would be enough for now. She contemplated a bit before finally saying,

"I see. Huh. Well, it doesn't appear you're being attacked right now, so how 'bout I go home and get dressed first and I'll come back? Sound good?" Marshall didn't want to be alone. Or, more importantly, for her to be. He knew she would kill Fionna too. He couldn't let that happen. Fionna waited for his answer, obviously not too concerned at the time being. Most evil beings like Marshall Lee didn't want to leave the Nighto'sphere and she knew that. Marshall sighed, finally coming to the conclusion that he simply couldn't let on it was her who was in danger.

"Yeah, okay. Hurry though." She nodded and hugged him. He held her tightly, resting his chin on her head and closing his eyes. His chest pounded, the beats picking up. He didn't want to let go.

"Umm, Marsh? You'll be fine, I got this." She wiggled out of his grip before running off towards the tree house. Marshall Lee turned and walked back into his house, collapsing onto his couch. He closed his eyes, sighing.

_Marshall Lee was spending the night at home. He lived in the tree house during this time, his girlfriend, Ashley, in the kitchen grabbing a snack. He was tuning his bass and it was raining. A loud boom echoed off the mountains. Marshall sat up quickly, putting his axe bass on the floor. That wasn't lightning and he knew it. She had done her deed. Marshall flew out the window, meeting his father before he reached the tree. He had been eating souls._

_"MARSHALL LEEEEE!" Marshall just waited, facing his father head on. "You released her into my domain? Why? Why would you do that? She let loose Gardsque! He's practically my child," his father hissed._

_"That BIRD is your child? Yeah, makes sense considering you love him more than me," Marshall sniffed._

_"I don't love him more than you, Marshall. But at least he's respectful of my authority."_

_"Ugh! You just don't get it, dad! I know about Marceline." Marshall's father went silent._

_"How did you find out about that?"_

_"It's nothing. Just go away." Marshall began to float back, tears coming to his eyes._

_"I'm sorry." Marshall stopped and turned, but his father was already a ways off in the distance, on his way to the Nighto'sphere._

_"What's going on?" Ashley called out. Marshall floated in the rain, completely soaked._

_"Nothing." He turned and went back inside..._

"Marshall! Wake up sleepy head!" Fionna stood over him, shaking him slightly. Her hair was combed now and she had fresh clothes and her green backpack.

"Huh? Oh, erg, did I fall asleep?" Marshall yawned, now needing the oxygen to survive.

"I guess so. Go comb your hair and we can get a goin'."

"Pfft, I don't need to comb my hair. This is what's cool, bro." Fionna rolled her eyes and he smiled. He was wearing a black t-shirt and jeans with his sneakers. He grabbed his red coat with the popped collar and big buttons.

"Let's go," he said before floating out the door.


	5. Into the Nighto'sphere

At first, Marshall let Fionna jog along side him, but he became impatient, wanting to fly there like he was so accustomed to. He could hear her deep breaths as she paced herself, always a good runner. Finally, unable to wait any longer, he flipped up-side down in the air, floating up above her as she ran. He reached down, grabbing her hand and floating up. Her legs kept moving for a moment, stopping as she realized she wasn't running anymore, but floating.

"Hey!" she said.

"We don't have time. I can fly there so much faster." Fionna huffed and glared out, but didn't protest, so he lifted her up, turning onto his stomach. He let her sit on his back as he flew there, Superman style. It was silent for the most part.

"Where are we goin' anyway?" Fionna asked after awhile.

"The Nighto'sphere."

"Well, pssht, I knew that. How do we get there?" Marshall frowned.

Well, there's a way to get there individually. But it only works for one person at a time and you can't do it unless you've used it to exit the Nighto'sphere. It brings you back to where you were, but since you've never been there, we'll have to use the big common entrance. Only those who know the codes, like I do, can pass."

"Huh. I see. So...how am I supposed to get in?"

"Easy. You'll just come in as my guest. You'll have to prove you're evil though. So I figured you could pretend to drink blood from a dead frog."

"Eww. Where the glob are we supposed to find a dead frog?"

"Easy. I have one in my pocket."

"What? You killed a little frog to get me into the Nighto'sphere?"

"Oh, c'mon man. It's not that bad. I AM an evil being, ya know. Plus, you only have to pretend. I actually have to drink the blood." Fionna gulped.

"Marsh?"

"Yeah?"

"Did you...did you used to drink blood?" Marshall was silent. He didn't respond and she sighed. They travelled along in silence a little bit longer. Fionna began to day dream...

_"Heeeelp!" Fionna was panting as she ran after him. This cave was impossible to navigate with all it's twists and turns. She didn't remember there being this cavern in the Ice Queen's home before, but then again, the Ice Queen was flippin' nuts. She was panting from running so much, listening for his cries of anguish and her evil cackles. Her laugh echoed down the corridor and Fionna ran down the path, determined to find them._

_"Leave him alone you crazy!" she yelled. She turned the corner, stepping into a gooey slime. "Ewww." She looked up from the slime, now following it along the floor. Blood trailed off to a body lying on the ground. He wore his usual pink outfit, his damaged crown on the floor next to him. "Prince Gumball! Ohglobohglobohglob," she cried, running towards him. An arrow pierced through his back. She grabbed him in her arms._

_"I love you, Fi." Fionna was crying hard, blubbery tears now, but something didn't seem right. Fi? She flipped him over on his back, his face turned towards her now. His skin had a slight green hue to it and his neck had its usual two scars. Black hair fell out of his face as she pushed it aside._

_"M-Marsh?" Marshall let out a final breath and Fionna let out an anguished cry..._

"There it is." Fionna shook her head, snapping out of the day dream. She looked down at where Marshall pointed. It was the Dark Forest, a forest often not adventured in. She had been there before. Bush Nose, their elephant friend that loved to bake apple pies, lived right outside of it. Fionna shuddered at the memory of the crystal guardians that had kidnapped her. Marshall Lee suddenly made a nosedive into the trees. Fionna wrapped her arms around his neck as he went into the forest. It was dangerously dark beneath the canopy. Marshall set her down, turning up right and standing before the oldest tree Fionna had ever seen. It was tall, towering over every other tree in the forest. It's trunk was huge and dark from age. Carved in the bark were strange symbols.

"What's with the weird symbols?" she asked.

"It's Latin."

"...What?" Marshall laughed.

"It's a really old language. It says, 'Entrance to the Night'." Fionna studied it for a moment. She always found interest in things from the time of humans. Her people...

Fionna shook her head, not wanting to think about it. There was always Tommy Tough. She was taken out of her trance as a cold hand wrapped around hers. She looked down at it. Marshall held her hand tightly as they walked towards the tree. She blushed and was tempted to pull away, but figured it was for her safety. The Nighto'sphere was a dangerous place.

"Patefacio ianua of nox noctis." Fionna looked up at Marshall as he said the words, her eyes bugging out. His age showed through more than ever and Fionna felt as though she was looking at an ancient artifact. She realized Marshall was her past. That he used to be human like her. The tree croaked and shook. Fionna took her ruby sword out, holding it tightly in her open hand.

"State your title and business." The ancient tree now looked down at them with mossy eyes that were dark but kind.

"Marshall Lee, Vampire King and son of the Dark Lord. We are here to see the ancient monster, Crevestia." The tree looked over at Fionna, it's body creaking as it moved.

"And the girl?"

"She is a guest."

"As set by the Lord of the Nighto'sphere, she must perform one evil act." Marshall slipped her the frog and she held it to her mouth, shaking it slightly as if it were alive. She made a cheesy sucking sound and Marshall quivered as he tried not to laugh. The ancient guardian didn't seem convinced, but nontheless he said, "Very well. Now you must do the same, supposed Vampire King." Marshall flew up and came back down with a bird. It chirped and struggled in his grasp. Fionna closed her eyes, not watching. Marshall's fangs slipped through it's neck with ease, sipping away it's blood in mere seconds. It went stiff and Marshall dropped it, now lifeless and solemn. "You are who you say you are. The last test is to recite the latin code of entry."

"Humanus fortis quod validus , pallens in mens , effrego terra , sic addo nos ut a domus of pacis , sub astrum quod in nox noctis. Luna nostrum era quod obscurum nostrum tepidus may Nighto'sphere exsisto nostrum sanctus subterlabor." The large tree closed it's eyes and rumbled, a rain of leaves falling down over them. A large door-like piece of bark opened and a pitch-black space existed beyond the opening. Marshall held Fionna's hand tightly as they walked forward, the darkness enveloping them. Fionna felt a strange calm come over her, but the journey was only beginning.


	6. King, Dad, and Soul-Eater

**Notes for the Chapter:**

> Marshall's dad is a pretty evil dude and a total douchenozzle in this chapter.

Fionna held close to Marshall's side, not sure where she was going. There was no floor, no ceiling, no walls. Marshall seemed perfectly fine. Despite the eerie nothingness of where they were, Fionna felt more at peace than ever. Like she was safe. In the Nighto'sphere, though? That can't be right, she thought.

"Marshall, this place is whack." Marshall smiled at her.

"You're confused, are you not?" Fionna looked ahead at the black, nodding her head. "You have to remember, my grandparents created the Nighto'sphere to be a peaceful place, not the dark, evil dump it is now. You can thank my father for that." Fionna contemplated a bit.

"So...is that why the guardian tree seemed so sweet?" Marshall nodded his head.

"Yeah. Will is actually really cool. He can't stand the new ordinances dad's put in place."

"Will?"

"Yeah, that's his name. Will the Willow Tree."

"That reminds me, what the lump was all that hoo-hah you said back there?"

"More Latin. It means, 'Humans brave and strong, weak in mind, break the land, so bring us to a home of peace, under stars and in the night. Moon our mistress and darkness our warmth, may the Nighto'sphere be our holy escape.'" Fionna scowled.

"Why do humans always have to be the bad guys? I'm a good guy! Er, gal. You get the point!" Marshall laughed at her frustration.

"Ready to get to the Nighto'sphere?" he asked.

"I thought we were already here?" He smiled wickedly at her. He suddenly tugged on her arm, pulling her into a tight embrace. He jumped, stomping down hard on the non-ground. Suddenly, they were falling into oblivion. Fionna gasped, closing her eyes and burrowing her head into Marshall Lee. Marshall laughed.

"Yo, it's fine." Fionna turned her head, looking out. Marshall floated perhaps 20 feet off the ground. The land was shrouded in darkness. A narrow path that dropped off dangerously low on the sides, led up to a large castle made of black stone and surrounded by a moat of acid and fire. Below, down in the dark valleys, people moaned. Fionna was confused. The Nighto'sphere looked tiny. As they flew towards the palace though, Fionna could see that everyone lived down in the valleys. Only one path led up from the valleys, alongside the cliff.

"So, uh, where are we going, exactly?" Fionna asked.

"My father knows I'm here. I have to go tell him I've arrived before we go down to the town." Fionna giggled.

"You made a rhyme." She started full out laughing now and Marshall rolled his eyes.

"Shut up, Fi." His cheeks began to turn red. Even when he was immortal they did this. He never understood why. They approached the gate now, landing in front of it. Two extremely large guards stood next to it. It was open, so Marshall walked past them and inside. One guard sniffed the air, following the scent to Fionna.

"Mmmmm, human," he said in a deep voice. Fionna shivered, but Marshall's arm around her waist made her feel comfortable. The courtyard was full of dead trees and zombie people wandered around, dressed in colonial-style clothing. They stared at Fionna, their soulless eyes piercing through her. Marshall stood in front of the door. A bat flew down, fluttering in front of Marshall.

"State your business, punk." Marshall glared at him.

"I'm here to see my dad, poo-brain," he hissed. The bat glared at him for a moment. With a poof, he turned into a vampire. He was very old, that was for sure. He wore the same clothes as the zombies, powder wig included.

"And herrrr?" The old vampire must know she's a human, Fionna thought. He smiled at her, flashing his fangs.

"She's a guest."

"You sure? She'd be a good gift for our Lord. Nice, pure, human soul." He leaned in towards Fionna, inhaling deeply. "Mmmmm. Delicious." Marshall hissed, pulling Fionna behind him and taking a slightly defensive stance. The old vampire chuckled. "Oh, lighten up red-sucker. You may pass. But no foolery." Marshall glared at him, but nodded, holding Fionna even closer to himself as they passed through the large, oak door. Fionna still held her ruby sword in her hand. The residents here obviously didn't care though, completely unaffected. They walked down a long corridor, lined with big pillars on each side. They entered through another set of large doors, coming into the kings room. At the end of the room was a stage with stairs leading up to it. There sat two thrones. The smaller one was empty. In the other sat Marshall's dad, wearing a business suit. A young, pretty ghost secretary was speaking to him when they entered. She stopped and floated away as Marshall's dad stared him down. He smiled.

"Marshall? My one and only son? Have you actually come to visit me?" Marshall seemed shocked by this, almost smiling for a moment.

"Um, uh, actually, I-"

"Hahaha! I kid, you know I don't like you coming here unannounced. But, as it has come to this, I suppose I'll deal with it." Marshall scowled again, closing himself off. The king sniffed the air. "What? What's that beautiful smell? Is that human? Have you actually brought me something, Marshall?"

"No. She's not food, she's my friend." His father laughed big and loud, as if he'd just heard the funniest thing in all of Aaa.

"Very funny, son. Now I'll just take her soul." He opened his mouth wide. It was lined with sharp teeth. Fionna took a defensive stance with her sword, but quickly began to lose strength as he sucked away her soul.

"DAD! Oh my glob, you are so embarrassing! Stop it!" Marshall pushed his dad, who stopped, allowing Fionna's soul to snap back to her. She was dizzy, but okay. "I'm serious! She really is my friend. She's helping me kill off Crevestia." Marshall's father now stared him down, thinking. He glanced at Fionna doubtingly, wobbly with her ruby sword.

"You actually expect to defeat her? With that girl's help? Ha! Even I could not defeat her. You will be killed in seconds! I don't want you doing this, Marshall." Marshall hissed and Fionna growled.

"I am not a weak girl! I am a brave fighter! I'll prove it to you!" Fionna yelled, ready to attack.

"Ugh! You never let me do anything! I'm an adult now so lump OFF!" Marshall turned and grabbed Fionna by her backpack. She struggled in his grip, swinging at the king. Marshall's face was bright red with anger. They exited the castle, now standing on the narrow path.

"I'll kill him!" Fionna yelled, still struggling.

"Forget it, Fi. He's not worth it. Thank glob THAT'S over. Let's go. I don't need his approval. I'm way stronger than him. He just thinks I'll get hurt because I'm mortal now." Fionna stopped struggling, looking up at Marshall.

"He knows?" Marshall looked away, ashamed.

"Yes. They all do. You can smell it. But being turned mortal is a terrible thing. It's not only embarrassing, but rude to point out. That's why they don't say anything. Even an outcast like me doesn't deserve such a thing as this, in their eyes." Fionna looked down, sorry she asked.

"Oh, jeeze. I'm sorry, Marsh..." Marshall looked at her, smiling. He put his finger under her chin, lifting her head up. He looked into her blue eyes.

"It's fine."

"Promise?"

"Promise. Now, lets go kick the guts out of some monsters."


	7. The Tomb of Good and Evil Evil-doers

Marshall grabbed Fionna up, flowing gracefully down into the dark valley on the left of the path. Little shacks and carts lay there, a few creatures stirring. They stared at the mortals as they passed by them. One rang a bell on his cart, signaling he was open for business. Merchants. The little flat-bottomed valley was small, with a tunnel going through the center path-cliff to the other valley. They didn't go over there though. Instead, they passed through the big stone wall that surrounded the castle and merchants. They were thick walls, causing the tunnel to be long. As they emerged on the other side, Fionna peered out at the land. It was a flat, dry wasteland with a few dead shrubs here and there.

"Ughhh. This place is worse than the valley of the dead," said Fionna.

"Yeah. This is where lost souls come. Those who are happy, go to the valley of the dead. But Death got tired of trying to sort out the confused, upset, and stubborn souls, so he made a deal with my dad. He'd send them here. My father feeds off of them."

"That's horrible!" Fionna stared at Marshall in horror who seemed completely unperturbed by this. They floated along a dirt path now, passing by the occasional shack and store. Most of anyone there was a ghost, but a few monsters would show themselves. The environment never seemed to change or falter and Fionna began to wonder where everyone was. The Nighto'sphere would have to be very large for all of it's inhabitants to live this widespread.

"Hey Marsh?"

"Mmm?"

"Where is everyone?" Marshall thought for a moment.

"Well, ghosts prefer to live out here because my father likes to go soul hunting in the cities. But my father will eat ANY soul, so the cities are farther away from the castle. You won't see any because the tomb of Good and Evil Evil-doers is in a small hill that'll be coming up soon. The closest city is probably Dark Alley. It's not the largest, that's for sure, but a lot of monsters live there. It's where the biggest, meanest ones live because they're less likely to be soul eaten. My father is busy and doesn't have time to fight them." Fionna thought for a minute. This made sense to her.

"How big is the tomb of Good and Evil Evil-doers?"

"From outside, not very big. It's a very small hill. But inside, it's a big labyrinth of tunnels and caves. That way, the monsters can't get out easily. My father has the only map, but I've gone with him to bury the creatures and have done a mental map of their burial spots. Especially hers."

"Why her?" Marshall stared forward at the path, unemotional.

"She is the 2nd most evil thing my father had ever met. She almost killed him."

"Who's the first?"

"The Ice Queen's penguin, Georgia. He claimed she was extremely dangerous, just stuck in the helpless body of penguin." They both laughed. They traveled along a little farther before coming across the only glitch in the repeating landscape. A small hill, perhaps only 10 feet tall, stood out from the ground. A carved doorway was in the side of the hill, going along with it's natural curve. They landed down in front of it. Marshall sucked in a big breath, letting it out slowly. Fionna glanced at the sign next to the doorway. The strange symbols were back. More Latin.

"Hey Marsh? What does that sign say?" Marshall didn't even have to look at it.

"Tomb of Good and Evil Evil-doers. No map. One entrance and exit. Enter with extreme caution." Fionna shivered at the words, inching closer to Marshall. He grabbed her hand and she blushed, but held on tight as they walked in through the doorway. The path was steep and shot down immediately. The cave was dark, so Fionna got out a candlestick and a match. She lit it and Marshall hissed.

"Oh, sorry! I didn't think this would hurt you!" She was about to put it out, but Marshall stopped her.

"No, the light stung my eyes, not my skin. I can automatically see in the dark. The sudden light hurt my eyes was all, but I'm fine now." Fionna looked at him, making sure. He smiled a sharp grin at her and she rolled her eyes.

"Wimp." Marshall stuck his tongue out at her.

"Oh really? You wanna prove that?" Marshall turned invisible.

"Maaarshhh. I'm so not in the mood for this right now." The candle suddenly went out and Marshall laughed darkly. It echoed and Fionna squinted, trying to see ahead of herself.

"Marshall, knock it off you dope!" She reached into her pack, grabbing out the matches. She lit it and screamed, jumping up and dropping the match. Marshall floated in front of her, his face formed into an ugly, twisted look. He laughed hard now, grabbing his stomach and shaking. She slapped him hard across the face, picking the match back up and lighting her candle.

"Hissss! Ow, what the glob Fionna?" Fionna scowled, walking quickly past him.

"That was NOT funny, Marshall!" Marshall smirked.

"Oh, c'mon, you would've laughed had it been someone else like, oh, say , PG for example."

"No, I would not have." Marshall snorted.

"That's because you liiike him." Fionna's face turned red.

"No I don't!"

"Yeeeah, you do!"

"NO I DON'T!" Marshall laughed. Fionna growled at him and was about to start wrestling him when a big, wet, slimy sound came from down the corridor.

SCCCHLICKKK!

They both froze, staring ahead.

"What was that?" Fionna asked.

"Crevestia." Marshall said. Both of their hearts pounded, but they kept going. Eventually, they came to a fork in the path. They took the left one, coming across more and more tunnels.

"So, uh, how is Crevestia alive?"

"Well, after I released her and she did what I wanted her to, my father threw her back in here. But when I fulfilled her curse, she gained enough power to break free of the stone binding. Now she's trying to find her way out so she can kill me."

"I don't get it. Why does she want to kill you?"

"It's an honor thing. Kill the Vampire King? That's a pretty big honor. Since she tried to defeat my father, she got locked in here. Otherwise, it wouldn't be such a big deal to kill someone since we're all evil."

"Huh. Weird. Where are we going?"

"Well, right now, towards her tomb. But she could be anywhere. She probably smells me and is trying to follow that to us." They walked along farther and farther. Fionna had lost track of where she was now, relying only on Marshall to get out. Suddenly, she stepped in some slime.

"Eww. What the-?"

"Crevestia. She's near." Fionna gripped her sword tighter. Her palms were sweaty despite the cold draft in the cave.

"You know who I wish was here? Cake," said Fionna. Marshall laughed.

"Um, no. She would claw the absolute crap out of my face." Fionna laughed this time. "But I bet she could scare every single monster in here just for getting close to you." Now they both laughed, still walking forward. The loud, wet noise came again, echoing off the cave walls behind them.

"Marshalll Leeee..," it whispered. Marshall whipped around, getting into a defensive stance. He hissed and a plump tentacle showed itself in the light. The creature put it down, pulling itself from around the corner and showing it's face in the light.


	8. The Battle to Save One Another

**Notes for the Chapter:**

> Violence in this chapter. I don't think it's too graphic, but if you've got a queasy tummy, just be careful.

Fionna shuddered at the sight of the ghastly creature. Eight plump, purple tentacles grew from it's body. They produced a slime that oozed from every seam, leaving puddles of the gooey gel. The creature had the torso of a human, but with greenish skin. She wore armor on her torso that was old and dirty, but looked strong and sturdy. Her head was shockingly beautiful, but so sharp in it's features that they almost hurt Fionna's eyes. Marshall was completely unperturbed by her. He had seen many things in his life, and Crevestia was nothing of surprise to his eyes. Her hair lifted and hissed, slithering snakes acting as deadly locks of hair.

"So, Marshall, you've fallen under my spell, have you? What a pity. I always thought you'd be stronger than that. Suppose I was wrong, wasn't I?" Marshall had relaxed ever so slightly, but still kept Fionna behind him. He watched her carefully, being careful so not to be affected by her petty words. Her mouth curved into a wicked grin and she looked at Fionna with her cold eyes. She shivered, but stood her ground.

"I see you've picked up a little friend. How cute. She smells wonderful. I can't _wait_ to eat her." Marshall glared at her and she chuckled. She sighed and with lightening speed, swiped at them. It happenend so fast, Fionna thought for sure Crevestia would get her tentacle around her waist and devour Fionna right on the spot. But Marshall's true power kicked in and he flew into the air with Fionna. Crevestia hissed, staring up at them. Marshall darted through the air around a corner, dropping Fionna off there.

"Stay here, Fi." He turned, about to leave.

"Wait!" she said, grabbing his hand. He turned to look at her, a look of pleading in his eyes. "I'm not going to just sit here and let you fight that thing by yourself. No flippin way." Marshall flew in close to her, putting his hand on her cheek. Her heart fluttered, but she didn't react.

"Please, Fionna." He looked into her eyes and she noticed that the red in them had dimmed down so low, they were almost gray now. Fionna remembered looking at pictures of Marsh as a child, his eyes a sharp blue. They almost reverted back to this now. She told herself it was because he probably hadn't had any red lately, but she knew the truth. He closed his eyes and lifted his mouth to her forehead. She took in a sharp breath and her face turned pink. He shot up into the air, turning around the bend to face Crevestia. She sat there for a moment, not breathing out.

Marshall turned very small, blowing out the torch on the wall so that the cavern became dark. Crevestia chuckled.

"Do you really think blowing out the light will keep me from killing you, Marshall Lee?" He flew up and along the wall. He was behind her as she looked around for him. He propelled himself from the wall now, attacking the monster. Her tentacles wrapped around him instantly and he hissed as she squeezed him. He bit into the large limb, ripping at it. She screeched and dropped him. He turned into a bat, flying up and above her. A snake swiped at him and hissed when it missed. Another one bit into his wing, ripping the fragile skin that stretched across it. He pulled away from the snakes and turned back to his normal figure. His arm bled ever so slightly from the bites. The blood built up, but Marshall licked it off to keep from dripping and revealing himself. Crevestia was obviously irritated now.

"Show yourself, parasite! Coward! Just like your _father_!" Marshall hissed without thinking, the hate for his father over riding his need to stay silent. "There you are!" she exclaimed. She whipped around and pulled out her bow, directing the deadly sharp arrow straight at Marshall.

"Marshall, look ou-" Fionna had come wandering back from her spot, sword in hand. But before he could move, it shot through the air and straight through Marshall's neck. He cried out in pain before collapsing to the ground.

"NO!" Fionna bolted over to his side.

"MWAHAHAHAHAHA! Foolish, mortal! You actually thought he could beat me in combat? Haha! You couldn't even figure out it was you who he fell for! He will now die all because of YOU!" Fionna turned to the monster, screaming out in anger. It was a scream full of pain, hurt, and fury. It was a scream that was unhuman, unmortal. Fionna swung her sword with impossible speed at the monster's neck. Crevestia hadn't expected the human to be quick enough to take her down, and with her guard off, she screeched in shock as the blade cut through her neck. Blood spurted out and on Fionna as Crevestia's head fell to the ground and rolled. The snakes hissed as they slowly withered up and died. Fionna didn't look at the dead thing twice. she turned to Marshall's limp and bleeding body. She collapsed to her knees by his side.

"Oh Glob, why? No, no, no, no! Please don't die, please." She cried big, blubbery tears. He moaned and she jumped. He was still alive! She picked him up and put him over her shoulder. He bled from the wound on his neck profusely. She ran through the tunnels, remembering that only Marshall knew the way out. She hopelessly wandered, running back through the places she had already been, leaving behind a trail of Marshall's blood. She knew she didn't have much time. Not to mention that she would probably end up dying in here too, seeing as there was no way out. "Please, help me Glob!"

She ran down the tunnel and tripped on a rock. She dropped her sword before falling through the floor. She yelled out for a second as they fell down what appeared to be an endless black pit. Now they really were gonners. Tears rolled off her cheeks and up, mixing in with the drops of blood. She grabbed onto Marshall, who was still unconscious.

"I love you, Marshall Lee!" She yelled. She closed her eyes and hugged onto him before she suddenly seemed to fall into her own unconscious realm...


	9. Happily Ever After in a Kitchen

Fionna was by herself now. She floated in what appeared to be a golden realm. She wore a long white dress and her hat was gone, her golden hair now hanging down low.

"He-hello?" she called out. A loud hoo echoed throughout the area and the Cosmic Owl appeared before her. She gasped as she took in it's grand beauty and godliness.

"Fionna the human," it said. She bowed her head as it spoke with it's deep voice.

"Yeah?"

"You have done this land many good deeds. You have never committed an evil act and have slayed both The Lich and the demon monster, Crevestia. Yet, my being as an angel of Glob has been awoken in distress. I feel that you are unhappy, young heroine. What is it that displeases you so?"

"My best friend is dying and I can't save him. He's not the best guy in the world and sure he's done some bad stuff, but I really think he's good! I know he is! Please Mr. Cosmic Owl, save him! Take me instead!" The Comic Owl studied the young girl for a moment before speaking.

"Fionna. You have willingly given your life in place of the Vampire King, Marshall Lee. However, Aaa still needs you and I cannot take your soul in his place." Fionna cried out, about to protest. Her chest seemed to be crushed with grief at the realization that she could not save Marshall Lee. "However," the Cosmic Owl began. "You will not be able to save this world unless you are happy. So in light of the fate of the world, I shall let the vampire live. He shall regain all of his immortality to ensure an event such as this is unlikely to happen again. Glob has payed you a great favor, young one. Be grateful by continuing to protect this world." Before Fionna could so much as thank the great owl, the whole world twisted itself into nothing and Fionna slipped back into a dreamless sleep.

Fionna blinked as the sun touched down on her face. She sat up in bed, looking around. It was late in the morning, later than what she usually woke at. She could smell bacon and Cake laughed cautiously, kind of how she did when Marshall Lee was over.

_Marshall Lee._

Had it all been a dream? She stood up and felt sore. It must've all happened. But how did she get home? And what happened to Marsh? She stumbled over to the ladder. She was going to find him, go find out what happened. The tree groaned ever so slightly and Cake's laughter stopped. Fionna turned the corner to the kitchen, rubbing her eye. Cake stood at the stove, frying bacon and hiding in the corner away from the sun coming through the window, floated Marshall Lee.

"Oh, hey baby! I was just about to wake you! You slept for a long time. About a whole day." Fionna just looked at Cake, the cat that was pretty much her sister.

"Wha-What happened?"

"Well, Marshall came over here covered in blood and a nasty looking scar on his neck. I was freaking out a bit because I thought he had hurt you." Marshall laughed.

"A bit?" Cake rolled her eyes, ignoring him.

"Anyway, you were in his arms unconscious. He was hysterical! He said that the last thing he remembered was being shot in the neck and falling. Then he woke up outside the portal to the Nighto'sphere covered in blood and you were laying next to him asleep. He knew the blood was his own, but he was pretty disoriented. He was actually crying." Cake giggled at that last part and Marshall gave her a death glare.

"I...I honestly thought you were dead. I didn't know how I could still be alive and when I felt my chest, my heart had stopped beating again. I wasn't thinking practically. I guess it should've been obvious since your heart was still beating and stuff..." He rubbed the back of his neck and he blushed. Fionna stared at him in shock. He was alive. She was alive. Everything was going to be okay.

And she loved Marshall.

Fionna ran to Marshall now, hugging him tightly. He gasped in surprise as she dug her face into his chest.

"Marshall...I thought I had failed. But...you're here." She looked up and into his eyes. They weren't red anymore, but a lovely blue that stood in stunning contrast against his black hair. He wrapped his arms around her now and Cake quietly left the room.

"Well, I'm here Fi. I'm alive. And you didn't fail. You saved me." Marshall looked down at her with as much love as he could. Now that he didn't have to worry about it, now that he knew they were safe and that they could be happy together.

"Marshall, you became mortal because of me, didn't you?"

"Yeah. I couldn't tell you, Fi. I was afraid Crevestia would sense that it was you. I was able to hide it from her until she shot me. After she did that, I lost control of my thoughts and she knew immediately."

"Marshall? I love you." Marshall looked at her silently as her face began to turn red and she looked away. He put his finger under her chin, turning her attention back at him.

"I love you too, Fi." Then he bent down and kissed her softly.

THE END

**Notes for the Chapter:**

> Awww, happy ending! However, you may have noticed there is another chapter. If this was too mushy-gushy, gooey-ooey for you, there is an alternate ending that ends much more tragically. If you were satisfied with the cheerful end, then you can just leave it at that or bear the horrifying OTP feels of this next chapter.


	10. (Alternate Ending!) The Acts of a Ghost

**Notes for the Chapter:**

> Again, this is an alternate ending and you can use whichever ending makes you feel happy and pretend this one didn't happen ~~even though it did~~

Fionna awoke in a a dark place. Marshall Lee lied strewn across her lap, still bleeding. She didn't know where she was or how she got there. A light appeared from the corner of her eye and it flashed. In it's place was a ghost with long flowing hair and simple features.

"Young human, when you fell into the abyss, you actually fell into my cell where I caught you and gently placed you here. I am the Ghost of Light and I was trapped here by the wicked ruler of the Nighto'sphere. I thank you for freeing me. For this, I shall grant you one request." Fionna didn't think twice.

"I want to save my dying friend!" The ghost looked at Marshall Lee who breathed shallow breaths now.

"Human girl, I'm afraid the only way to save your friend is to offer him the life of another." Fionna looked at Marshall in desperation.

"What...what about my life?"

"You are a mortal and thus, the vampire boy you wish to save shall become mortal much like you." Fionna looked at Marshall a final time before deciding. She looked at the ghost with determination and closed her eyes as she spoke.

"Then I choose to give my mortal life to Marshall Lee." Marshall opened his eyes now, looking up at Fionna as she said the words that would let him live.

"No!" he whispered, barely able to speak. But it was too late. Fionna began to glow and Marshall felt a fuzzy warmth begin to grow within him. There was a flash and everything went dark. Marshall opened his eyes, blinking a few times. He was laying on his side and the only light came from a hole far up in the ceiling. Suddenly, he remembered what had just happened.

"Fionna!" He yelled. He sat up and looked over his shoulder. Lying on the ground, just a silouette in the dark cell, lied the girl he loved. He ran to her, bending over her lifeless body. He rolled her over and looked into her peaceful face. Tears streamed down his cheeks and he couldn't see anything.

"NOOOOOOOOOOOO!" He screamed out before collapsing over her, his whole body shaking with sobs.

Marshall walked to the funeral, umbrella in hand. He had to dig pretty far into his closet to find this over-sized suit. He thought back to when he had taken Fionna back home to Cake. She had collapsed to her knees without a word. They both sat there and cried, even though Cake was still scared of him. You just didn't take that kind of stuff into consideration when you're that filled with grief. He had called Bubba too. Bubba acted very formal but solemn over the phone, saying he'd arrange a small funeral for her. But Marshall had been right outside his window and when the oh-so proper prince had hung up, he had sat on his bed, head in his hands, and cried softly. Marshall was at the top of the hill now and could see the small gathering of Fionna's closest friends at the bottom, surrounding her gravestone. He joined them now as Bubba said a few words. Amoung them were Cake, of course, and Lord Monochromicorn. B-MO stood there too and Lumpy Space Prince floated next to Prince Gumball. When Bubba went silent, they all just sat there and stared at her grave.

Cake sobbed and Gumball sniffled here and there. The first one to leave was LSP. Lord M followed shortly, inviting Cake over later if she wanted some comforting. Soon, Prince Gumball picked up B-MO and he slowly walked away. The sun was setting behind them when Cake finally turned away and walked home. Marshall still stood there staring at her tombstone. He took his umbrella and folded it up, not needing it anymore.

"When my heart starting beating for you, I almost died. And when all seemed lost, you didn't give up. You gave your own life so that I could live mine." Marshall placed his hand over the scar on his neck, oppisite his bite marks, that marked the place he had been shot.

"And now, my heart beats _because_ of you. I will live this new, mortal life of mine to it's fullest. I will do good and protect Aaa much like you did. For you. Because of you." Marshall now placed his hand on his chest where his new, mortal heart beat.

"I love you, Fi, and I always will." He took something from his back pocket and set it in front of her gave before opening back up his umbrella and walking away into the sunset. The colors in the clouds made the white bunny hat now sitting on her grave, glow ever so slightly. On her tombstone it said,

"RIP Adventurer and Heroine Fionna 'Fi' the Human."

THE (Sad) END


End file.
